Or

If you have studied how to solve a system of linear equations Using Substitution or by solving Simultaneous Linear Equations you know that you usually get two values as an answer. But why is that, why don’t you just get a single value as an answer? By graphing a system of linear equations we will be able to better visualize what the solution of a system of equations is and why it is written the way it is.

Learn this and go on to Functions/Combining Functions
17
Tutorials That Teach Solving Linear Systems by Graphing

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